We previously found that Pleurotus ferulae polysaccharides (PFPS) improved the maturation and function of dendritic cells (DCs). In this study, we investigated the effects of PFPS on the antitumor efficacy of therapeutic human papillomavirus (HPV) DC-based vaccine. PFPS stimulated DCs pulsed with HPV E6/E7 peptides were used to treat tumor mice on day 5 & 12 (HPV + PFPS-DCs early) and day 12 & 19 (HPV + PFPS-DCs late) after TC-1 cell injection. Compared to control group, both HPV + PFPS-DCs early and HPV + PFPS-DCs late strategies significantly inhibited tumor growth, which was significantly correlated with the increased activation status of both CD4+ and CD8+ T cells, the decreased frequencies of myeloid-derived suppressor cells, and the induction of HPV-specific CD8+ T cell responses. The survival of tumor mice was also greatly improved by HPV + PFPS-DCs early. Moreover, HPV + PFPS-DCs early completely inhibited the growth of second challenged TC-1 cells in tumor free mice. The results showed that PFPS improved the antitumor efficacy of therapeutic HPV DC-based vaccine, suggesting that PFPS might be a potential adjuvant for DC-based vaccines. This study provides a potential strategy for developing the therapeutic DC-based vaccine against cervical cancer.
Keywords: polysaccharides; antitumor efficacy; dendritic cell; human papillomavirus; vaccine.